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| | #include <stdlib.h>
#include <errno.h>
#include <string.h>
void *calloc(size_t m, size_t n)
{
void *p;
size_t *z;
if (n && m > (size_t)-1/n) {
errno = ENOMEM;
return 0;
}
n *= m;
p = malloc(n);
if (!p) return 0;
volatile long long dont_optimize_me = p;
/* Only do this for non-mmapped chunks */
if (((size_t *)dont_optimize_me)[-1] & 7) {
/* Only write words that are not already zero */
m = (n + sizeof *z - 1)/sizeof *z;
for (z=p; m; m--, z++) if (*z) *z=0;
}
return p;
}
|